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Environment, Environnement, Pollution, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Pollution du sol et des sédiments, Soil and sediments pollution, Décontamination. Divers, Decontamination. Miscellaneous, Chlore Composé organique, Chlorine Organic compounds, Cloro Compuesto orgánico, Cinétique, Kinetics, Cinética, Constante vitesse, Rate constant, Constante velocidad, Cosolvant, Cosolvent, Cosolvente, Déchloration, Dechlorination, Descloración, Décontamination, Decontamination, Descontaminación, Dégradation chimique, Chemical degradation, Degradación química, Epuration eau usée, Waste water purification, Depuración aguas servidas, Epuration physicochimique, Physicochemical purification, Depuración fisicoquímica, Ethanol, Etanol, Ethylène(tétrachloro), Ethylene(tetrachloro), Etiléno (tetracloro), Extraction solvant, Solvent extraction, Extracción solvente, Fer, Iron, Hierro, Hydrocarbure chloré, Chlorocarbon, Hidrocarburo clorado, In situ, Lavage, Washing, Lavado, Liquide non aqueux, Nonaqueous phase liquid, Líquido no acuoso, Matériau modifié, Modified material, Material modificado, Matériau revêtu, Coated material, Material revestido, Modification chimique, Chemical modification, Modificación química, Métal zérovalent, Zerovalent metal, Metal cerovalente, Nickel, Niquel, Performance, Rendimiento, Pollution sol, Soil pollution, Polución suelo, Produit dégradation, Degradation product, Producto degradación, Solvant mixte, Mixed solvent, Disolvente mixto, Traitement surface, Surface treatment, and Tratamiento superficie

Remediation of sites contaminated by chlorinated organic compounds is a significant priority in the environmental field. Subsequently, the addition of cosolvent solutions for in situ flushing of contaminated source zones has been successfully field tested. However, the treatment of effluent fluids in such cleanup efforts is an often overlooked component of this technology implementation. The purpose of this research was to evaluate the effectiveness of zero-valent iron (Fe0) in treating perchloroethylene (PCE) in an aqueous solution, and how the presence of a cosolvent (ethanol) and modification of the iron surface altered dechlorination. The modified iron surfaces included in this study were nickel-plated iron, acid-treated iron, and untreated iron surfaces. PCE dechlorination in the presence of each of the iron surfaces displayed pseudo first-order kinetics. The highest degradation rate of PCE occurred on the nickel-plated iron surface, 0.00583 h-1, followed by the acid-treated iron, 0.00492 h-1, and the untreated iron, 0.00334 h-1. Dechlorination on each of the surfaces decreased with increasing cosolvent fractions. It was shown that as cosolvent fractions increased, PCE adsorption decreased and resulted in a concomitant decrease in PCE degradation rates.

Environment, Environnement, Pollution, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Batiment. Travaux publics, Buildings. Public works, Durabilité. Pathologie. Réparation. Entretien, Durability. Pathology. Repairing. Maintenance, Divers, Miscellaneous, Pollution, Déchets, Wastes, Déchets divers et constituants particuliers des déchets, Other wastes and particular components of wastes, Abrasion, Abrasión, Décapage, Pickling, Decapado, Déchet dangereux, Hazardous waste, Residuos peligrosos, Déchet solide, Solid waste, Residuos sólidos, Exposition professionnelle, Occupational exposure, Exposición profesional, Lixiviation, Lixiviación, Métal lourd, Heavy metal, Metal pesado, Méthode essai, Test method, Método ensayo, Nettoyage mécanique, Mechanical cleaning, Limpieza mecánica, Nettoyage surface, Surface cleaning, Limpieza superficie, Peinture plomb, Lead paint, Pintura plomo, Performance, Rendimiento, Plomb, Lead, Plomo, Produit bâtiment, Building product, Producto construcción, Protection personne, Person protection, Protección persona, Sablage, Sand blasting, Enarenación, Sable, Sand, Arena, Scorie, Slag, Escoria, Stabilisation, Stabilization, Estabilización, Teneur, Content, Proporción, Traitement déchet, Waste treatment, Tratamiento desperdicios, Traitement surface, Surface treatment, Tratamiento superficie, and Laitier charbon

A study was conducted to demonstrate the effectiveness of a wet abrasive blasting technology to remove lead-based paint from exterior wood siding and brick substrates as well as to evaluate the effectiveness of two waste stabilization technologies to stabilize the resulting blast media (coal slag and mineral sand) paint debris thereby reducing the leachable lead content. The lead-based paint removal technology effectiveness was determined by the use of an X-ray fluorescence (XRF) spectrum analyzer (L- and K-shell). The effectiveness of the technologies to stabilize the debris was evaluated through the toxicity characteristic leaching procedure (TCLP). Wet abrasive blasting effectively removed the lead-based paint coating from both the wood and brick substrates to below the US Department of Housing and Urban Development Guideline (1 mg/cm2) with no minimal or no damage to the underlying substrates (P<0.0001). The mean area air levels of lead-containing particulate generated during paint removal were significantly below the personal exposure limit (PEL) (P<0.0001). However, the mean personal breathing zone lead levels were approximately three times higher than the PEL. Neither of the two stabilization technologies consistently stabilized the resultant paint debris to achieve a leachable lead content below the RCRA regulatory threshold of <5 mg/l.

Environment, Environnement, Pollution, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Traitement et pollution des eaux, Water treatment and pollution, Réutilisation des eaux usées. Divers, Wastewaters reuse. Miscellaneous, Déchets, Wastes, Autres déchets industriels. Boues résiduaires, Other industrial wastes. Sewage sludge, Aluminium Sulfate, Aluminium Sulfates, Aluminio Sulfato, Aluminium, Aluminio, Ammonium Sulfate, Ammonium Sulfates, Amonio Sulfato, Caractérisation, Characterization, Caracterización, Cristallisation, Crystallization, Cristalización, Diffraction RX, X ray diffraction, Difracción RX, Déchet industriel, Industrial waste, Desperdicio industrial, Déchet liquide, Liquid waste, Residuo líquido, Eau usée industrielle, Industrial waste water, Agua servida industrial, Finissage surface, Surface finishing, Hydrate, Hydrates, Hidrato, Matière première, Raw materials, Materia prima, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Optimisation, Optimization, Optimización, Performance, Rendimiento, Préparation, Preparation, Preparación, Réutilisation déchet, Waste reuse, Reutilización desperdicios, Solution acide, Acidic solution, Solución ácida, Spectrométrie ICP, Inductive coupling plasma spectrometry, Espectrometría ICP, Traitement surface, Surface treatment, Tratamiento superficie, Valorisation, Upgrading, Valorización, and Al(NH4)(SO4)2.12H2O

Experimental tests were conducted in the present study to investigate synthesis of aluminum ammonium sulfate (aluminum alum) by crystallization from the waste acid solution of aluminum surface finishing industry. Effects of various operating conditions including the molar ratio of ammonia and aluminum ion, temperature, mixer speed, seed alum dosage, initial sulfuric acid and aluminum ion concentrations on the aluminum alum formation, crystal size distribution, acid remaining and aluminum ion removal were examined. The crystallization process was found to be quite effective in recovering resource materials (sulfuric acid and aluminum) in the form of aluminum alum from the waste acid solution. Based on the test results, optimum operating conditions were recommended for efficient operation of the crystallization process.

Environment, Environnement, Pollution, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Traitement et pollution des eaux, Water treatment and pollution, Eaux usées, Wastewaters, Eaux usées industrielles, Industrial wastewaters, Aluminium, Aluminio, Dialyse, Dialysis, Diálisis, Eau usée industrielle, Industrial waste water, Agua servida industrial, Epuration eau usée, Waste water purification, Depuración aguas servidas, Epuration physicochimique, Physicochemical purification, Depuración fisicoquímica, Etude technicoéconomique, Technicoeconomic study, Estudio técnicoeconómico, Industrie métallurgique, Metallurgical industry, Industria metalúrgica, Membrane échangeuse anion, Anion exchange membrane, Membrana cambiadora aniónica, Performance, Rendimiento, Solution acide, Acidic solution, Solución ácida, Sulfurique acide, Sulfuric acid, Sulfúrico ácido, Séparation par membrane, Membrane separation, Separación por membrana, Traitement surface, Surface treatment, and Tratamiento superficie

Diffusion dialysis with anionic ion exchange membranes was employed to recover sulfuric acid from the waste acid solution of aluminum surface processing plant. Experiments were conducted to examine the dialyzer performances under various operating conditions, including feed flow rates, sulfuric acid concentration in the feed solution, temperature and number of pieces of ion exchange membrane. Diffusion dialysis was found very efficient for this purpose. Based on the test results, optimum operating conditions of these variables were identified. Preliminary economic evaluation of the process indicated that diffusion dialysis is highly viable for sulfuric acid recovery due to its short payback period.